I think the graphics were fantastic, SNES or not. How old they are might matter more had 2D not died just a few years later. Personally, I can only imagine the graphics of those two games being considered better from an artistic and/or subjective viewpoint, as from a technical viewpoint, they certainly aren't better, PSIV's cutscenes exempted.
for me it might of had more to do with the actual attack animations. i guess after playing shining force 2 they looked too cheesy for me and far too pixelated. clearly the snes was capable of better. out of curiosity was ff6 the last FF game to have a female lead before ff12? perhaps if i had tried ff6 right when it came out instead of after playing crono trigger and seiken densetsu 3 i would of felt differently.